Clinical significance of activity of ALT enzyme in patients with hepatitis C virus

Abstract

Aim: To investigate serum alanine aminotransferase (ALT) levels in relation to the clinical, biochemical, ultrasonographic and histological characteristics of patients with hepatitis C virus.

Methods: Duration of disease, HCV-RNA, liver steatosis, and the hepatitis activity index (HAI) were correlated with serum ALT in 36 patients with HCV. ALT values were also investigated in 16 control subjects without any liver diseases.

Results: In bivariate analyses, ALT levels correlated with duration of HCV infection (P < 0.01), HCV-RNA (P < 0.05), and the HAI (P < 0.01). Among the components of the HAI, ALT concentrations were significantly associated with periportal bridging/necrosis (P < 0.01) and fibrosis (P < 0.05). In multivariate analysis, periportal bridging/necrosis (beta = 0.508; P < 0.01), duration of HCV infection (beta = 0.413; P < 0.01), and HCV-RNA (beta = 0.253; P < 0.05) were independently associated with ALT activity. The normal ALT activity for men and women was < 23 IU/L and < 22 IU/L, respectively.

Conclusion: In patients with HCV, alterations in the liver tissue as reflected by ALT elevation are mainly associated with periportal bridging/necrosis, viral load and duration of disease. A cut-off value < 23 IU/L distinguished with high diagnostic accuracy healthy controls from patients with HCV.

Figure 1

Scatter diagram and regression line showing a significant positive relationship between duration of HCV infection and serum alanine aminotransferase (r = 0.46, P < 0.01).

Figure 2

Scatter diagram and regression line showing a significant inverse relationship between viral load and serum alanine aminotransferase (r = -0.33, P < 0.05).

Figure 3

Scatter diagram and regression line showing a significant positive relationship between the Histology Activity Index and serum alanine aminotransferase (r = 0.44, P < 0.01).

Figure 4

ROC curve of serum ALT for discriminating female HCV patients from women without liver disease. The better cutoff value for ALT was at 22 IU/L, with sensitivity of 87.5% and specificity of 100% in identifying subjects without HCV infection.

Figure 5

ROC curve of serum ALT for discriminating male HCV patients from men without liver disease. The better cutoff value for ALT was at 23 IU/L, with sensitivity of 100% and specificity of 100% in identifying subjects without HCV infection.